1. Field of the Invention
The present invention relates to an imaging apparatus, more specifically, an imaging apparatus in which a lens unit and a body unit are detachably attached to each other and configured to be connected with each other by a plurality of different communication interfaces, and also relates to a lens unit which is capable of efficiently sending image data to a body unit, an imaging apparatus including the lens unit, and an imaging method.
2. Description of the Related Art
There is known an imaging apparatus including a lens unit housing a photographing lens, an imaging device, and a CPU (Central Processing Unit) configured to perform a predetermined image processing, and a body unit capable of detachably connecting the lens unit, the body unit having a CPU configured to perform a predetermined image processing, and a recording section for image data.
In such an imaging apparatus, it is necessary to transfer various data between the CPUs mounted on the lens unit and the body unit. Therefore, the imaging apparatus is configured such that communication between the CPUs is performed via a shared memory.
That is, the conventional imaging apparatus has a configuration in which the lens unit and the body unit are connected by a data bus.
In order that the lens unit and the body unit are connected by the data bus and have a configuration to be capable of communicating with each other, there is a problem in that a resist on a substrate is exposed in a part to join the lens unit and the body unit.
Further, in the connection by the data bus, a generalized connector cannot be used for a connection interface. Therefore, there is a problem in that the manufacturing cost becomes high.
Furthermore, a circuit configuration of a part connected by the data bus becomes complicated. Therefore, there is a problem in that the number of components of the part connected by the data bus increases.
In order to solve such problems, there is known an imaging apparatus configured such that a lens unit is connected to a body unit by a generalized serial port (for example, refer to Japanese Patent Laid-Open Publication Number 2007-110314).
An imaging apparatus described in Japanese Patent Laid-Open Publication Number 2007-110314 is configured such that transfer of data between CPUs included in a lens unit and a body unit is performed by a serial driver for a control to perform a bidirectional communication and a serial driver for an image to perform a unidirectional communication from the lens unit to the body unit.
When operating in a body side recording mode, the imaging apparatus in Japanese Patent Laid-Open Publication Number 2007-110314 sends image data of a formed image from the lens unit to the body unit via the serial driver for the image.
Further, when operating in a lens side recording mode, the imaging apparatus in Japanese Patent Laid-Open Publication Number 2007-110314 records the image data of the formed image on a recording section included in the lens unit, generates a thinned data image or reduced data image based on the recorded image data, and sends the thinned data image to the body unit to be displayed on a monitor.
Since data volume of the thinned data image is reduced compared to that of an original image, even the generalized serial driver for the control is capable of sending the thinned data image.
As mentioned above, volume of the image data to be sent from the lens unit to the body unit is reduced, and thereby the imaging apparatus disclosed in Japanese Patent Laid-Open Publication Number 2007-110314 can perform the transfer of the image data between the CPUs by use of the generalized serial driver for the control.
However, in order to send the image data by use of the generalized serial driver for the control, it is necessary to determine in advance a data format of the image data to be sent from the lens unit to the body unit. That is, when the thinned data image is generated, it is necessary to perform a processing to convert the image data into data in a single data format. Therefore, the data format of the image data to be sent from the lens unit to the body unit is fixed and cannot be changed, and there is a problem in that a restriction arises to a type of the data format of the image data to be handled and a data size, that is, an image size of the image data to be handled.
Further, a problem arises in that image quality is lowered because data of the thinned data image is used as the image data to be sent and/or received.
Normally, in an imaging apparatus including a lens unit housing an imaging device, and a body unit which is capable of detachably connecting the lens unit, when the lens unit is replaced by a different lens unit, the imaging device housed in the lens unit is also replaced by a different imaging device, and in a case where the different imaging device is used, a different data format and a different data size of image data are used.
That is, in an imaging apparatus which is constituted such that a lens unit and a body unit are detachably attached to each other, since a data format and a data size of image data to be sent from the lens unit to the body unit are fundamentally in a variety of types, it is preferable that the image data to be sent from the lens unit to the body unit also correspond to the various data formats and the various data sizes.
However, in a case of providing with the body unit a function corresponding to the image data of a plurality of the data formats and the data sizes, a cost thereof becomes high. Further, although there is also a way to handle the various data formats by updating a processing program in accordance with the lens unit to be attached, an operation becomes cumbersome and inconvenient.